Q. Write an explicit formula that represents the sequence defined by the following recursive formula:a1=8 and an=3an−1Answer: an=
Identify Recursive Formula: The given recursive formula is a1=8 and an=3an−1. This indicates that each term is three times the previous term, which suggests that the sequence is geometric.
Use Geometric Sequence Formula: For a geometric sequence, the nth term is given by the formula an=a1×r(n−1), where a1 is the first term and r is the common ratio.
Determine First Term and Ratio: We know the first term a1=8 and the common ratio r=3 (since each term is three times the previous term).
Substitute Values into Formula: Substitute the values of a1 and r into the formula for the nth term of a geometric sequence to get the explicit formula.an=8×3(n−1)
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